Vehicle mirror device

ABSTRACT

A holding member integrally includes a bearing pair that rotatably support at least one gear of rotation-force transmission mechanism.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present document incorporates by reference the entire contents ofJapanese priority document, 2005-356302 filed in Japan on Dec. 9, 2005.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicle mirror device including arotatable mirror.

2. Description of the Related Art

Vehicle mirror devices with a rotatable mirror have been used. Forexample, Japanese Patent Application Laid-Open No. 2004-182117 disclosesa vehicle mirror device that includes a worm gear rotatably supported bya separate bearing member and a gear that meshes with the worm gear.When the worm gear is rotated, a vehicle mirror is rotated via the gear.

However, in the conventional vehicle mirror device, the worm gear issupported by the separate bearing member, and therefore, rotationfluctuation and inclination of the worm gear may occur.

SUMMARY OF THE INVENTION

It is an object of the present invention to at least partially solve theproblems in the conventional technology.

According to an aspect of the present invention, a vehicle mirror devicethat includes a rotatable mirror, includes a holding member thatincludes a bearing member, a rotation-force transmission mechanism thatincludes a plurality of gears, and a bearing that is integral with thebearing member and rotatably supports at least one of the gears.

According to another aspect of the present invention, a vehicle mirrordevice that includes a mirror rotatable with respect to a vehicle body,includes a shaft that is fixed to the vehicle body, a rotation drivingunit that is rotatably supported by the shaft, and a mirror assemblythat includes the mirror and is attached to the rotation driving unit.The rotation driving unit includes a holding member that includes abearing member, and is rotatably supported by the shaft and attachedwith the mirror assembly, a motor that is attached to the holdingmember, a rotation-force transmission mechanism that includes aplurality of gears, and drives the motor to rotate the mirror assemblywith respect to the shaft, the rotation-force transmission mechanismbeing located between the motor and the shaft, and a bearing that isintegral with the bearing member and rotatably supports at least one ofthe gears.

The above and other objects, features, advantages and technical andindustrial significance of this invention will be better understood byreading the following detailed description of presently preferredembodiments of the invention, when considered in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cutaway plan view of a vehicle mirror device according to anembodiment of the present invention;

FIG. 2 is an exploded perspective view of an electric retracting unitshown in FIG. 1;

FIG. 3A is a plan view of a gear portion of a first worm gear of thevehicle mirror device;

FIG. 3B is a schematic sectional view taken along line B-B in FIG. 3A;

FIG. 3C is a side view of the gear portion of the first worm gear;

FIG. 3D is a schematic side view of the gear portion of the first wormgear;

FIG. 4A is a schematic front view of a pin serving as a shaft of thefirst worm gear;

FIG. 4B is a plan view of the pin;

FIG. 5A is a schematic front view of a helical gear as a first gear ofthe vehicle mirror device;

FIG. 5B is a schematic sectional view taken along line B-B in FIG. 5A;

FIG. 5C is a schematic sectional view taken along line C-C in FIG. 5A;

FIG. 6A is a front view of a second worm gear of the vehicle mirrordevice;

FIG. 6B is a plan view of the second worm gear;

FIG. 7 is a schematic for explaining the process of temporarily fixingthe gear portion of the first worm gear to a temporary fixing member ofa plate;

FIG. 8 is a schematic for explaining the process of press-inserting thepin into a hole of the gear portion and a bearing pair of the plate;

FIG. 9 is a schematic for explaining the process of housing asub-assembled plate, the first worm gear, the helical gear, and thesecond worm gear into a gear case;

FIG. 10 is a schematic for explaining a state where the first worm gear,the helical gear, and the second worm gear of a deceleration mechanismare housed in a housing partitioned by the gear case and the plate;

FIG. 11 is a schematic for explaining the process of setting the helicalgear between a pair of elastic bearings of the plate;

FIG. 12 is a schematic for explaining a state where an elastic bearingpair of the plate is opened outward and elastically deformed with theentrance of the helical gear;

FIG. 13 is a schematic for explaining the process of inserting arotation shaft of the second worm gear into a through hole of thehelical gear supported by the elastic bearing pair;

FIG. 14 is a schematic for explaining the process of housing thesub-assembled plate, the first worm gear, the helical gear, and thesecond worm gear into the gear case;

FIG. 15 is a schematic for explaining a state where the first worm gear,the helical gear, and the second worm gear of the deceleration mechanismare housed in the housing; and

FIG. 16 is a schematic for explaining a state where the second worm gearis inclined with respect to the helical gear.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Exemplary embodiments of the present invention are explained in detailbelow with reference to the accompanying drawings.

A structure of a vehicle mirror device 1 according to an embodiment ofthe present invention is explained referring to FIG. 1. In thisembodiment, the vehicle mirror device 1 is, for example, an electricretractable door mirror device. The vehicle mirror device 1 is mountedon each of left and right doors (not shown) of a vehicle. The vehiclemirror device 1 includes a shaft 4, a rotation driving unit (an electricretracting unit) 3, and a mirror assembly 2.

The shaft 4 is fixed to both the left and right doors of the vehicle.The rotation driving unit 3 is rotatably attached to the shaft 4. Amirror 5 is attached to the mirror assembly 2 via an attaching member 6.The mirror assembly 2 is attached to the rotation driving unit 3.

When the mirror assembly 2 is rotated around the shaft 4 via therotation driving unit 3, the- mirror 5 rotates with respect to the leftand right doors of the vehicle, i.e., a vehicle body.

As shown in FIG. 2, the shaft 4 is integrally formed with a flange 7extending vertically thereon. The shaft 4 and the flange 7 constitute ashaft holder 8. The shaft holder 8 is fixed to a mirror base 9 shown inFIG. 1. The mirror base 9 is fixed to the left and right doors of thevehicle. Thus, the shaft 4 is fixed to the left and right door of thevehicle. The shaft 4 is formed in a hollow shape such that a harness(not shown) is inserted through the shaft 4.

The rotation driving unit 3 includes, as shown in FIG. 2, a gear case10, a plate 11, and a cover 12 as a holding member, a motor 13, and adeceleration mechanism 14 and a clutch mechanism 15 as a rotation-forcetransmission mechanism.

As shown in FIGS. 2, 9, 10, 14, and 15, the gear case 10 is closed onone side (lower side) with an opening on the other side (upper side) toform a concave in section. The gear case 10 includes the concave as ahousing 16. The housing 16 is closed on the shaft holder 8 side with anopening on the plate 11 and the cover 12 side to form a concave insection. An insertion hole (not shown) is formed on the closed side ofthe gear case 10. The shaft 4 is inserted in the insertion hole. As aresult, the gear case 10 is rotatably attached to the shaft 4. A ball 17and a washer 18 are interposed between the closed side of the gear case10 and the flange 7 of the shaft holder 8.

As shown in FIG. 2 and FIGS. 7 to 16, the plate 11 has a substantiallyflat shape to close the opening of the housing 16 of the gear case 10. Acircular through hole 19 is formed on one side of the plate 11. A motorhousing 20 of a cylindrical shape with an opening on one side (upperside) is formed integrally with the other side of the plate 11. Themotor 13 is housed and fitted in the motor housing 20. A concave housing21 is formed integrally with the bottom of the motor housing 20 at thecenter. An output shaft (not shown) of the motor 13 and a joint 22attached to the output shaft are housed in the housing 21. Three baseattaching pieces 23 are formed integrally with the edge of the openingof the motor housing 20. A base 24 is attached to the base attachingpieces 23.

The plate 11 is fitted in the opening of the housing 16 to close theopening thereof. The shaft 4,is inserted through the through hole 19 ofthe plate 11. The plate 11 is fixed to the gear case 10 by a screw orthe like (not shown). As a result, the plate 11 is rotatably attached tothe shaft 4 together with the gear case 10.

As shown in FIG. 2, the cover 12 is closed on one side (upper side) withan opening on the other side (lower side) to form an inverted concave insection. That is, the cover 12 includes an inverted concave housing (notshown). The housing is opened on the side of the gear case 10 and theplate 11 below the housing and closed on the upper side. Aharness-through cylindrical hole 25, which communicates with the throughhole 19, is formed integrally with the cover 12. The cover 12 is fittedand fixed to the outside edge of the opening of the housing 16. Thus,the plate 11, the motor 13, the deceleration mechanism 14, the clutchmechanism 15, and the base 24 are housed in the housing 16 covered bythe cover 12. The cover 12 is rotatably attached to the shaft 4 togetherwith the gear case 10 and the plate 11.

As shown in FIG. 2, the deceleration mechanism 14 and the clutchmechanism 15 as the rotation-force transmission mechanism are housed inthe housing 16 between the output shaft of the motor 13 and the shaft 4.The deceleration mechanism 14 and the clutch mechanism 15 transmit arotation force of the motor 13 to the shaft 4.

The deceleration mechanism 14 includes a first worm gear 26, a helicalgear 27 that meshes with the first worm gear 26, a second worm gear 28that meshes with the helical gear 27, and a clutch gear 29 that mesheswith the second worm gear 28. The first worm gear 26 is coupled to theoutput shaft of the motor 13 via the joint 22 in the housing 21 of theplate 11.

The clutch mechanism 15 includes the clutch gear 29, a clutch holder 30,a spring 31, and a push nut 32. In the clutch mechanism 15, a washer 33,the clutch gear 29, the clutch holder 30, and the spring 31 aresequentially fitted to the shaft 4. The spring 31 is compressed by thepush nut 32. A recess (or projection) formed in the clutch gear 29engages with a projection (or a recess) formed in the clutch holder 30.By engagement between the second worm gear 28 of the decelerationmechanism 14 and the clutch gear 29 of the clutch mechanism 15, arotation force of the motor 13 is transmitted to the shaft 4. The spring31 is a coil spring and shown in FIG. 2 in a simplified form.

The first worm gear 26 includes, as shown in FIGS. 2 to 4B and FIGS. 7to 10, a gear portion 41 and a pin 42 serving as a shaft. As shown inFIGS. 3A to 3D, a worm gear is provided on the outer surface of acolumnar member of the gear portion 41. A circular hole 43 is formed inthe center of the gear portion 41 (the columnar member).

As shown in FIGS. 4A and 4B, the pin 42 is formed by machining a pinmember. One end of the pin 42 (the pin member) is chamfered to form acoupling portion 44 including two planes substantially parallel to eachother. A supporting portion 45 in a semispherical shape at the endthereof is provided at the other end of the pin 42. A fixing portion 46formed by parallel knurling is provided at the center of the columnarpin 42. Shaft portions 47 are provided on both sides of the fixingportion 46.

The pin 42 is pressed into the hole 43 of the gear portion 41 from thecoupling portion 44 side (see FIG. 8) to interlock and fix the fixingportion 46 of the pin 42 to the inner surface of the hole 43. Thus, thefirst worm gear 26, which rotates together with the gear portion 41 andthe pin 42, is formed (see FIGS. 9 and 10).

As shown in FIGS. 5A to 5C, the helical gear 27 integrally includes agear portion 48 and shaft portions 49.

The shaft portions 49 are formed integrally with both sides of the gearportion 48 via a step portion 50. The helical gear 27 also includes athrough hole 51 in a rotation center direction. On the inner surface inthe middle of the through hole 51 is provided a contact portion 52having two straight sides parallel to each other and being partially ina non-circular shape. The contact portion 52 has a slight width in therotation center direction. A curved side connects between the paralleltwo straight sides of the contact portion 52, and forms a part of thecircular arc. The inner surface of the through hole 51 is tapered fromboth the ends toward the middle, i.e., the contact portion 52, to form adrum shape in section.

As shown in FIGS. 6A and 6B, the second worm gear 28 integrally includesa gear portion 53 and a rotation shaft 54. Spherical projections 55 areformed integrally with both ends of the rotation shaft 54, respectively.Shaft portions 561, 562, and 563 are formed at both the ends and in themiddle of the rotation shaft 54. An outer diameter of the shaft portion561 at one end is smaller than that of the shaft portion 562 in themiddle and the shaft portion 563 at the other end. On an externalsurface of the rotation shaft 54 between the shaft portion 561 and theshaft portion 562 is provided a contact portion 57 having two planesurfaces parallel to each other and being partially in a non-circularshape. A surface connecting the parallel two plane surfaces of thecontact portion 57 forms a part of the columnar shape.

A distance L1 from one end of the rotation shaft 54 to a step portion570 between the shaft portion 562 and the contact portion 57 is longerthan a distance L2 in the rotation center direction of the shaftportions 49 of the helical gear 27. Consequently, when assembled witheach other, the helical gear 27 and the second worm gear 28 are in anon-contact state in a thrust direction. As shown in FIGS. 14 and 15, agap S is formed between the end faces of the shaft portions 49 of thehelical gear 27 and the step portion 570 of the second worm gear 28. Thefirst worm gear 26 and the helical gear 27 constitute a worm gear and agear. The helical gear 27 and the second worm gear 28 constitute a firstgear and a second gear.

A bearing pair 34 and an elastic bearing pair 35 are formed integrallywith the plate 11. The plate 11 constitutes one bearing member. As shownin FIGS. 7 to 10, the bearing pair 34 support the shaft portions 47 atboth ends of the pin 42 of the first worm gear 26 to be rotatablesubstantially around a vertical axis. The bearing pair 34 include thebottom of the housing 21 and a portion opposed to the bottom to bevertically spaced apart from the bottom. A vertical space L3 between thebearing pair 34 is larger than a length L4 of the columnar gear portion41 of the first worm gear 26. Circular through holes 36 are formed inthe vertical direction in the bearing pair 34, respectively. A temporaryfixing member (a temporary placing member) 37 is provided between thebearing pair 34. The bearing pair 34 and the temporary fixing member 37are opened on one side (right side in FIGS. 7 to 10) and closed on theother side (left side in FIGS. 7 to 10) to form a concave. An opening 38is formed in the bottom of the concave, i.e., the temporary fixingmember 37. A length L5 of the opening 38 is smaller than the length L4of the gear portion 41 and larger than a length L6 of the worm gear ofthe gear portion 41.

As shown in FIGS. 7 to 16, the elastic bearing pair 35 support thehelical gear 27 to be rotatable substantially around the horizontalaxis. The elastic bearing pair 35 include two elastic plates opposed toeach other to be horizontally spaced apart on the lower surface of theplate 11. A horizontal space L7 between the elastic bearing pair 35 islarger than a width L8 of the gear portion 48 of the helical gear 27 andshorter than a length L9 in the rotation center direction of the shaftportions 49. The elastic bearing pair 35 are adjacent to the bearingpair 34 and the temporary fixing member 37 on the left and the right ofthe bearing pair 34 and the temporary fixing member 37. Circular throughholes 39 are formed in the horizontal direction in the elastic bearingpair 35, respectively. The elastic bearing pair 35 have inclined planes40 from lower sides to the middle of the through holes 39 on opposedsurfaces thereof, respectively.

As shown in FIGS. 9, 14, and 15, thrust bearings 58 that respectivelyreceive thrust forces of the spherical projections 55 at both ends ofthe rotation shaft 54 are formed in the gear case 10. Specifically, asshown in FIG. 9, the thrust bearings 58 are provided in a lower portionof a guide groove 59 that tapers from the opening to the bottom of thehousing 16 of the gear case 10.

As shown in FIGS. 11 to 15, radial bearings 60 and 61 that receiveradial forces of the shaft portions 562 and 563 of the rotation shaft 54are provided in the gear case 10 and the plate 11, respectively. Asshown in FIGS. 9 and 10, the gear case 10 includes a receiving portion62 that receives the supporting portion 45 of the pin 42 of the firstworm gear 26. As shown in FIGS. 14 and 15, the gear case 10 alsoincludes grooves 63 in which lower portions having the inclined planes40 of the elastic bearing pair 35 are inserted. When the lower portionsof the elastic bearing pair 35 are inserted in the grooves 63, theelastic bearing pair 35 and the gear case 10 are integrated and reliablysupport the helical gear 27 without opening and closing the elasticbearing pair 35.

A process of assembling the first worm gear 26, the helical gear 27, andthe second worm gear 28 of the deceleration mechanism 14 in the gearcase 10 and the plate 11 as the holding member is explained below.

As indicated by a solid line arrow in FIG. 7, the gear portion 41 of thefirst worm gear 26 is set in the bearing pair 34 and the temporaryfixing member 37 of the plate 11. Then, as shown in FIG. 8, the gearportion 41 is located between the bearing pair 34 and temporarily fixed(temporarily placed) by the temporary fixing member 37. In other words,the columnar gear portion 41 is temporarily fixed by the temporaryfixing member 37 and the worm gear of the gear portion 41 is located inthe opening 38. The gear portion 41 can be set easily by dropping thegear portion 41 with the temporary fixing member 37 side (left side ofFIGS. 7 and 8) on the lower side.

As indicated by a solid line arrow in FIG. 8, the shaft portions 47 andthe fixing portion 46 are press-inserted into the through holes 36 ofthe bearing pair 34 and the hole 43 of the gear portion 41 from thecoupling portion 44 side. Then, as shown in FIG. 9, the shaft portions47 of the pin 42 are rotatably supported by the bearing pair 34. Thefixing portion 46 is interlocked and fixed to the inner surface of thehole 43. Thus, the first worm gear 26 with the gear portion 41 and thepin 42 rotating together is constituted. Consequently, the first wormgear 26 is rotatably supported by the bearing pair 34 of the plate 11.

Subsequently, as indicated by solid line arrows in FIGS. 11 and 12, theshaft portions 49 of the helical gear 27 are opposed to the elasticbearing pair 35. The helical gear 27 is pressed into the space betweenthe elastic bearing pair 35. Then, the shaft portions 49 contact theinclined planes 40 and enter into the space along the inclined planes40. At this point, as indicated by solid line arrows in FIG. 12, theelastic bearing pair 35 are elastically deformed outward and opened.When the shaft portions 49 reach the through holes 39 of the elasticbearing pair 35 as shown in FIG. 13, the elastic bearing pair 35, whichhave been elastically deformed outward, elastically return inward andclose to the original state. As a result, the shaft portions 49 areinserted into the through holes 39 of the elastic bearing pair 35 thathave returned to the original state.

Thus, the gear portion 48 is set between the elastic bearing pair 35.The shaft portions 49 are elastically held and rotatably supported bythe elastic bearing pair 35. At this point, as shown in FIGS. 9 and 10,the gear portion 41 of the first worm gear 26 and the gear portion 48 ofthe helical gear 27 mesh with each other through the opening 38 of theplate 11.

As indicated by a solid line arrow in FIG. 13, the end on the contactportion 57 side of the second worm gear 28 is opposed to the helicalgear 27 rotatably supported by the elastic bearing pair 35. At thispoint, the radial bearings 61 of the plate 11 are located between thehelical gear 27 and the second worm gear 28. The rotation shaft 54 (thespherical projection 55, the shaft portion 561, and the contact portion57) is inserted into the through hole 51 of the helical gear 27. Then,as shown in FIGS. 14 and 15, the contact portion 57 of the rotationshaft 54 and the contact portion 52 of the through hole 51 come intocontact with each other.

Consequently, the second worm gear 28 is temporarily held by the helicalgear 27. The mutual contact between the contact portion 52 of thehelical gear 27 .being partially in a non-circular shape and the contactportion 57 of the second worm gear 28 allows the helical gear 27 as thefirst gear and the second worm gear 28 as the second gear to rotatetogether. At this point, as shown in FIGS. 14 and 15, the two shaftportions 562 and 563 holding the gear portion 53 of the second worm gear28 are located in the two radial bearings 61, respectively. A part ofthe gear portion 53 is housed in the recess between the two radialbearings 61.

In this way, the first worm gear 26 (the worm gear) and the helical gear27 (the gear) of the deceleration mechanism 14 (the rotation-forcetransmission mechanism) are rotatably supported by the plate 11 (onebearing member). The second worm gear 28 (the second gear) of thedeceleration mechanism 14 is temporarily held by the helical gear 27(the first gear). Thus, as shown in FIGS. 9 and 14, the first worm gear26, the helical gear 27, and the second worm gear 28 are sub-assembledwith the plate 11.

As indicated by the solid line arrows in FIGS. 9 to 14, the first wormgear 26, the helical gear 27, the second worm gear 28, and the plate 11sub-assembled each other are set in the housing 16 in a drop-in manner.Then, as shown in FIGS. 10 and 15, the first worm gear 26, the helicalgear 27, and the second worm gear. 28 sub-assembled with the plate 11are housed in the housing partitioned by the gear case 10 and the plate11.

Consequently, the supporting portion 45 of the first worm gear 26 isthrust-supported by the receiving portion 62 of the gear case 10. Theelastic bearing pair 35 are inserted into the grooves 63 of the gearcase 10. Thus, the shaft portions 49 are reliably supported by theelastic bearing pair 35. In addition, the shaft portions 562 and 563 ofthe second worm gear 28 are radially supported by the radial bearings 60of the gear case 10 and the radial bearings 61. The sphericalprojections 55 at both ends of the second worm gear 28 are supported bythe thrust bearings 58 of the gear case 10.

At this point, the helical gear 27 and the second worm gear 28 are in anon-contact state in the thrust direction. As shown in FIG. 15, the gapS is formed between the end faces of the shaft portions 49 of thehelical gear 27 and the step portion 570 of the second worm gear 28.

As described above, the first worm gear 26, the helical gear 27, and thesecond worm gear 28 of the deceleration mechanism 14 are assembled withthe gear case 10 and the plate 11 as the holding member. Then, the motor13 is attached to the plate 11. The output shaft of the motor 13 and thefirst worm gear 26 are coupled via the joint 22. The clutch mechanism 15is assembled with the shaft 4 and the gear case 10. The cover 12 isattached to the gear case 10. Consequently, the rotation driving unit 3is rotatably attached to the shaft 4. The mirror assembly 2 is attachedto the rotation driving unit 3. Thus, the vehicle mirror device 1 as anelectric retractable door mirror device is constituted. The shaft 4 isfixed to the left and right doors of the vehicle.

Consequently, the vehicle mirror device 1 is mounted on the left andright doors (not shown) of the vehicle.

The vehicle mirror device 1 according to this embodiment is constitutedas described above. The operation of the vehicle mirror device 1 isexplained below.

First, an in-vehicle switch (not shown) is operated to drive the motor13. Then, a rotation force of the motor 13 is transmitted to the clutchgear 29 fixed to the shaft 4 via the output shaft, the joint 22, and thedeceleration mechanism 14. At this point, the clutch gear 29 isunrotatably fixed to the shaft 4. Therefore, the second worm gear 28 ofthe deceleration mechanism 14 rotates around the clutch gear 29. Thisrotation rotates the mirror assembly 2 including the rotation drivingunit 3 around the shaft 4. With this rotation, as shown in FIG. 1, it ispossible to rotate the mirror assembly 2 between a position for use (aposition in the state of FIG. 1) and a retracted position B. When themirror assembly reaches the position for use or the retracted positionB, power supply to the motor 13 is cut off by a switching operation of aswitching mechanism (not shown). As a result, the mirror assembly 2stops at the predetermined position for use and the retracted positionB.

When loads are applied to the mirror assembly 2 from the front side orthe rear side, the clutch gear 29 rotates against a pressing force ofthe spring 31. As a result, engagement between the projection and therecess of the clutch gear 29 and the clutch holder 30 is released.Consequently, the mirror assembly 2 rotates due to buffering between theposition for use and the retracted position B or between the positionfor use and a forward inclined position A.

Because the contact portion 52 of the helical gear 27 and the contactportion 57 of the second worm gear 28 contact with each other, thehelical gear 27 as the first gear and the second worm gear 28 as thesecond gear can rotate together. As a result, the rotation force istransmitted between the helical gear 27 and the second worm gear 28.

The inner surface of the through hole 51 is tapered from both the endstoward the middle. Therefore, when the rotation force of the motor 13 istransmitted to the shaft 4 via the deceleration mechanism 14 and theclutch mechanism 15, the second worm gear 28 can incline from a normalstate indicated by an alternate long and two short dashes line to astate indicated by a solid line in FIG. 16. On this occasion, becausethe inner surface of the through hole 51 is tapered from both the endstoward the middle, even if the second worm gear 28 inclines with respectto the rotation center, this does not affect the helical gear 27.

As set forth hereinabove, according to an embodiment of the presentinvention, the vehicle mirror device 1 includes the bearing pair 34formed integrally with the plate 11 as one bearing member, and the firstworm gear 26, as at least one gear of the rotation-force transmissionmechanism, including the gear portion 41 and the pin 42 as the shaftportion. The gear portion 41 is set between the bearing pair 34, and thepin 42 is press-inserted and rotatably fixed to the bearing pair 34 andthe gear portion 41. Besides, the vehicle mirror device 1 includes theelastic bearing pair 35 formed integrally with the plate 11, and thehelical gear 27, as at least one gear of the rotation-force transmissionmechanism, including the gear portion 48 and the shaft portions 49. Thegear portion 48 is set between the elastic bearing pair 35, and theshaft portions 49 is elastically and rotatably held by the elasticbearing pair 35. The first worm gear 26 and the helical gear 27 thatmeshes with the first worm gear 26 are thereby rotatably supported bythe bearing pair 34 and the elastic bearing pair 35 of the one plate 11,respectively. Therefore, the rotation center axes of the first worm gear26 and the helical gear 27 is accurately located. Thus, it is possibleto reliably prevent rotation fluctuation and inclination of the firstworm gear 26 and the helical gear 27. Consequently, a pitch between theaxes of the first worm gear 26 and the helical gear 27 is stabilized.This reduces operation noise, and improves a product value anddurability performance. In addition, the first worm gear 26 and thehelical gear 27 can be sub-assembled with the plate 11. As a result,efficiency of assembling the deceleration mechanism 14 as therotation-force transmission mechanism and the gear case 10 and the plate11 as the holding member is improved.

Moreover, dimensional accuracy management for the holding member isperformed by the one plate 11. Thus, it is possible to reduce cost forthe dimensional accuracy management for components and realize areduction in a schedule for commercialization.

Furthermore, the gear case 10 includes the grooves 63 in which lowerportions of the elastic bearing pair 35 are inserted. When inserted intothe grooves 63, the elastic bearing pair 35 are integrated with the gearcase 10. As a result, it is possible to reliably support the helicalgear 27 without opening and closing the elastic bearing pair 35.

Moreover, the thrust bearings 58 receive thrust forces of the sphericalprojections 55 at both ends of the rotation shaft 54 of the second wormgear 28 as the second gear. The helical gear 27 as the first gear andthe second worm gear 28 are in a non-contact state in the thrustdirection. That is, as shown in FIG. 15, the gap S is formed between theend faces of the shaft portions 49 of the helical gear 27 and the stepportion 570 of the second worm gear 28. As a result, when the mirror 5is rotated with respect to the vehicle body (the door) via the mirrorassembly 2, even if a thrust force acts on the second worm gear 28, athrust force of the second worm gear 28 does not affect the helical gear27. Consequently, the mirror assembly 2 (the mirror 5) can smoothly andreliably rotate. Therefore, the helical gear 27 does not need highstrength. Accordingly, it is possible to reduce manufacturing cost andimprove durability performance of the helical gear 27. In particular,when a force of an input from the second worm gear 28 is large, thiseffect is large.

Furthermore, the inner surface of the through hole 51 is tapered fromboth the ends toward the middle. Thus, even if the helical gear 27 orthe second worm gear 28 inclines with respect to the rotation center,this does not affect the second worm gear 28 or the helical gear 27.Therefore, noise is prevented and durability performance is improved.Additionally, because of the shape of the inner surface of the throughhole 51, the rotation shaft 54 can be easily inserted into the throughhole 51. Therefore, it is easy to assemble the helical gear 27 and thesecond worm gear 28 and assembly work is improved.

Moreover, a slight gap allowing the helical gear 27 and the second wormgear 28 to rotate together is formed between the contact portion 52 ofthe helical gear 27 and the contact portion 57 of the second worm gear28. That is, positions of the helical gear 27 and the second worm gear28 are not regulated by each other. Consequently, a radial force of thesecond worm gear 28 does not affect the helical gear 27. Further, thedimension of the through hole 51 and the rotation shaft 54 need not behighly accurate, which reduces manufacturing cost.

Incidentally, in the embodiment described above, the present inventionis applied to the electric retractable door mirror device. However, thepresent invention can be applied to other vehicle mirror devicesincluding vehicle outside mirror devices such as a vehicle fender mirrordevice and vehicle inside mirror devices such as an in-vehicle mirrordevice.

In the above embodiment, the spherical projections 55 at both ends ofthe rotation shaft 54 of the second worm gear 28 as the second gear arethrust-supported by the thrust bearings 58 of the gear case 10. However,both ends of the rotation shaft (the shaft portion 49) of the helicalgear 27 as the first gear can be thrust-supported by the thrust bearingof the holding member. Also, both ends of the rotation shafts of boththe first gear and the second gear can be thrust-supported by the thrustbearing of the holding member.

In the above embodiment, the helical gear 27 as the first gear includesthe through hole 51, the inner surface of which is tapered from both theends toward the middle, and the second worm gear 28 as the second gearincludes the rotation shaft 54 inserted into the through hole 51.However, conversely, the through hole can be provided in the second gearand a rotation shaft inserted into the through hole can be provided inthe first gear.

Although the invention has been described with respect to a specificembodiment for a complete and clear disclosure, the appended claims arenot to be thus limited but are to be construed as embodying allmodifications and alternative constructions that may occur to oneskilled in the art that fairly fall within the basic teaching herein setforth.

1. A vehicle mirror device that includes a rotatable mirror, the vehiclemirror device comprising: a holding member that includes a bearingmember; a rotation-force transmission mechanism that includes aplurality of gears; and a bearing that is integral with the bearingmember and rotatably supports at least one of the gears.
 2. The vehiclemirror device according to claim 1, wherein the bearing memberintegrally includes a pair of bearings, and the gears include a wormgear that includes a gear member that is located between the pair ofbearings; and a shaft pin that is rotatably arranged between the pair ofbearings and pressed into a hole of the gear member to be rotatabletogether with the gear member.
 3. The vehicle mirror device according toclaim 1, wherein the bearing member integrally includes a pair ofelastic bearings, and the gears includes a first gear that integrallyincludes a gear member that is located between the pair of elasticbearings; and a shaft that is elastically and rotatably supported by thepair of elastic bearings.
 4. The vehicle mirror device according toclaim 1, wherein the bearing member integrally includes a pair ofbearings and a pair of elastic bearings, the gears includes a worm gearand a first gear that meshes with the worm gear, the worm gear includesa gear member that is located between the pair of bearings; and a shaftpin that is rotatably arranged between the pair of bearings and pressedinto a hole of the gear member to be rotatable together with the gearmember, and the first gear integrally includes a gear member that islocated between the pair of elastic bearings; and a shaft that iselastically and rotatably supported by the pair of elastic bearings. 5.The vehicle mirror device according to claim 1, wherein the bearingmember integrally includes a pair of elastic bearings, the gearsincludes a first gear that integrally includes a gear member that islocated between the pair of elastic bearings; and a shaft that iselastically and rotatably supported by the pair of elastic bearings, andthe holding member includes grooves where the pair of elastic bearingsare arranged.
 6. A vehicle mirror device that includes a mirrorrotatable with respect to a vehicle body, the vehicle mirror devicecomprising: a shaft that is fixed to the vehicle body; a rotationdriving unit that is rotatably supported by the shaft; and a mirrorassembly that includes the mirror and is attached to the rotationdriving unit, wherein the rotation driving unit includes a holdingmember that includes a bearing member, and is rotatably supported by theshaft and attached with the mirror assembly; a motor that is attached tothe holding member; a rotation-force transmission mechanism thatincludes a plurality of gears, and drives the motor to rotate the mirrorassembly with respect to the shaft, the rotation-force transmissionmechanism being located between the motor and the shaft; and a bearingthat is integral with the bearing member and rotatably supports at leastone of the gears.
 7. The vehicle mirror device according to claim 6,wherein the bearing member integrally includes a pair of bearings, andthe gears include a worm gear that includes a gear member that islocated between the pair of bearings; and a shaft pin that is rotatablyarranged between the pair of bearings and pressed into a hole of thegear member to be rotatable together with the gear member.
 8. Thevehicle mirror device according to claim 6, wherein the bearing memberintegrally includes a pair of elastic bearings, and the gears includes afirst gear that integrally includes a gear member that is locatedbetween the pair of elastic bearings; and a shaft that is elasticallyand rotatably supported by the pair of elastic bearings.
 9. The vehiclemirror device according to claim 6, wherein the bearing memberintegrally includes a pair of bearings and a pair of elastic bearings,the gears includes a worm gear and a first gear that meshes with theworm gear, the worm gear includes a gear member that is located betweenthe pair of bearings; and a shaft pin that is rotatably arranged betweenthe pair of bearings and pressed into a hole of the gear member to berotatable together with the gear member, and the first gear integrallyincludes a gear member that is located between the pair of elasticbearings; and a shaft that is elastically and rotatably supported by thepair of elastic bearings.
 10. The vehicle mirror device according toclaim 6, wherein the bearing member integrally includes a pair ofelastic bearings, the gears includes a first gear that integrallyincludes a gear member that is located between the pair of elasticbearings; and a s haft that is elastically and rotatably supported bythe pair of elastic bearings, and the holding member includes grooveswhere the pair of elastic bearings are arranged.